Is Power Steering Fluid The Same As Transmission Fluid?

Last Updated:
Is Power Steering Fluid The Same As Transmission Fluid

The hydraulic system in your car requires hydraulic fluids to perform optimally. Note that the moving parts produce excess friction and heat that damage your engine components. It also attracts dust and particles that can easily clog up.

The hydraulic fluids come in handy to remove the contamination and lubricate the engine parts. It also allows heat transfer, sealing, and energy transmission. Among the main hydraulic fluids include the power steering fluids and the automatic transmission fluids (ATF). Read more to understand their uses, differences, and if you can substitute them.

Why change your power-steering fluid?

The power steering wheel not only lubricates the moving parts but also helps to transfer power between the steering wheel and the automobile’s front wheels. It can only serve the purpose if it’s in a suitable condition.

Regular frushing is vital since, with time, oil attracts grits and dust. These grits thicken and harden with time and damage both the rack and the piston seals. So, always check the level and condition of the fluid when doing regular car maintenance. Change the fluid if it’s old or has attracted grits and dust.

Power steering fluid (PSF) vs ATF

Maybe you intend to change the fluid but are confused about the type of fluid to buy. Worry less. Here is a comparison of power steering fluid vs atf to help you know if you can use both interchangeably.

The main differences between these fluids are the color, functions, and formulation. A new ATF fluid will come with a red color and a unique sweet smell. After using it for a long, the color will change to orange or even dark.

You can’t confuse the sweet smell of the ATF with the burnt marshmallow-like smell of the PSF. You will see a clear, pinkish/amber color in a new PSF, but it will turn red/brown after long use.

Remember, among the main functions of ATF is lubricating, thus preventing excess heat buildup in the engine due to friction. It also cleans debris and grease, thus protecting the system from clogging. This fluid can perform these roles thanks to the detergent and the friction regulator in it.

The PSF doesn’t have the ingredients in the ATF but has oil that lubricates the power steering components, thus reducing the friction. It also ensures that there is no heat-build up that can easily damage the components.

Can you use transmission fluid for power steering pump?

It depends on the model of the car that you have. Some owner manual comes with strict instruction not to use transmission fluid on the power steering pump. After all, the detergents become harmful to the pump seals and destroy the components.

Some companies such as Toyota don’t mind the users using the Dextron III ATF. So, whenever you require to replace the fluid, the manual is helpful.

Is it possible to replace the PS fluid with transmission fluid In any vehicle?

Maybe you are a new car owner, and you know the importance of regular car maintenance. You wouldn’t want to make a decision that could jeopardize the safety of your car. You visit the nearest auto shop, and there is ATF with no PSF. So, can you use transmission fluid for power steering fluid? Read below to understand. 

Some mechanics don’t want to incur a high cost of keeping these two hydraulic fluids in their garage. As a result, they keep one and use it when doing the regular car maintenance of different cars. Are they wrong? That depends on the make of your car, year of manufacturing, and the manual.

Modern high-tech vehicles come with strict instructions and recommend the use of PS fluid strictly. An attempt to substitute will be a disservice to you since you risk the components getting damaged. That comes with severe repair costs that you could have avoided.

Before the ’90s, the owners of models such as Ford cars had no problem substituting the two. So, if you still have that make, you can still substitute.  Most Toyota cars also have no problem replacing the PS fluid for the Dextron III ATF.

Can you mix power steering fluid with transmission fluid?

Maybe you have decided to flush the fluid at home, but the PS fluid available is not enough. The neighbor next door has a little ATF and is offering to give you. But the question remains, can you mix power steering fluid? Check below to know more.

Someone may argue that there is no problem since both are hydraulic fluids. But remember that both have different compositions and may negatively affect your car if you mix them. PSF has oil and may cause the rubber seal in the system to expand. As a result, the fluids may start leaking. Again, there are some models strictly designed to work with the PS fluid. So, if you include the ATF, you will have a hard time trying to shift gears.

The complications that may result from mixing the two may be costly; the mechanic will suggest you flash the system, replace broken parts and buy the right fluid. So, unless you mix them by mistake, avoid mixing them completely.

Difference between brake fluid and power steering fluid?

Just like the PS fluid, the brake fluid is also a hydraulic fluid. Knowing the differences will help you to avoid mixing or confusing the two. You can use the brake fluid in your truck, motorcycle, or even a bicycle. It helps to amplify the pressure you apply on the foot pedal all over the car, forcing it either to slow or even stop. That contrasts with the use of PS fluid that lubricates the hydraulic system.

You are already wondering what their composition is; as explained above, the PSF has oil that helps to lubricate the system. The brake comprises glycol-ether, mineral oil, or even silicon.

The composition helps the braking fluid to power up the braking components. Instead of power, the PSF pressures the car’s steering system.

The brake fluid remains incompressible regardless of the environmental changes. As a result, it has a high boiling point compared to the power steering fluid. The higher boiling point helps in ensuring that the consistency of the brake pedal won’t change.

The freezing point of the PS fluid is a bit low compared with the ATF. Remember, the fluid can never freeze and become stone-like water. But at low temperatures, it becomes gel-like.

How do you know if you need a power steering fluid?

Maybe you have taken so long without either changing the PS fluid or even checking its level. Below are some of the signs you will see if fluid is either low or has overstayed.

1. Change of color

Initially, the color of the flesh power steering fluid is either pinkish or umber. But once it oxidizes, the color turns to red and later to black. Once you see this color change, the best option is to change the fluid immediately.

2. Difficult turning wheel

You will have a hard time steering also once the level lowers. Among the reasons that cause this includes low PS fluid or an issue with the drive belt.

3. Loud steering

Are you experiencing some strange noises in the steering? Then there should be a problem. The steering wheel makes noises, mostly when the brake fluid is less.  Once you hear the strange noise, change the oil immediately.

4. Vibrating & jerky steering wheel

Another sign that the fluid is low is the jerky steering or even vibration. That’s risky since making sharp turns can be impossible or difficult. So, address the challenge immediately by parking the car and calling the mechanic. You can also call the towing company to take your vehicle to the mechanic instead.

5. Leaking fluid

Leaking fluid is another leading cause of low fluid. So, if you had filled the steering power pump and it’s already empty, you need to address the leaking problem immediately.

6. Bubble’s

Another indicator that the there is PS fluid is low is the presence of bubbles. Bubbles indicate that there is a linkage; thus, the problem requires an immediate address.

What are power steering fluid specification standards?

Before buying the steering fluid, you must ascertain that it’s the correct fluid for your car. Remember, different models come with strict specifications. The European vehicle requires you to use synthetic-based fluid that meets ISO 7308 or even DIN 51 524T3. These standards were developed by the German institute of standardization.

This standard gives specific instructions concerning the viscosity, detergent, and the right amount of additive.

What does power steering fluid do?

The main work of the power steering fluid is lubricating the system, thus preventing excess friction that results from moving parts that rub each other. That saves on the cost since you will not have to replace engine parts since there is little or no wear and tear. The next role is linking the front wheels of your car to the steering wheel.


1. What can I use if I don’t have power steering fluid?

If you urgently require changing the power transmission fluid, but it’s not currently available, then consider these substitutes.  ATF is the first substitute and is perfect for cars of the years 1980-2000. Other car companies recommend the use of this fluid. Other substitutes that you can use temporarily include the DEXRON Transmission fluid and the MERCON transmission fluid.

2. Is power steering fluid universal?

Don’t get confused that all the PS fluids are universal. It’s upon you to check the manual and know the right one for your car. Again, you may also consider if your car requires you to use the ATF.

3. Is it OK to mix different brands of power steering fluid?

You can mix them so long as the fluid that you are topping up with is the right fluid recommended by the manufacturer. However, remember never to mix the red and green steering fluid.


You should never ignore changing or checking the transmission fluid level in your car. After all, many signs appear when the fluid is low or even old. You will hear some strange voices from the steering or even some vibration from the engine. You will also have difficulty turning wheels. Leaking or bubbles are other signs that the fluid is low. Knowing the correct fluid to add is vital. The owner’s manual is clear on the type of hydraulic fluid to include. Some models are okay with ATF, while most modern vehicles strictly recommend the use of the PSF. The reason being, that the ATF has some detergents that sneak into the system and ruin the parts. Also, be careful when mixing the fluids. Avoid mixing the ATF and the PSF.

Leave a Comment